As stated in the original application of the grant, the goal of this program is to develop 7-10 day renal preservation which will be necessary for optimum donor-recipient matching. In the first 9 months of the grant, we have looked at two possible causes of preservation damage. In studying kidneys preserved by cryoprecipitated level, it was noted that the adenine nucleotides slowly but continuously decreased. If the total nucleotide decreases below a certain level, it is known that the kidney will not recover after transplantation. In order to alter the level of total adenine nucleotides in perfused kidneys, we are in the process of adding a number of compounds that are involved in the synthesis and breakdown of these high energy compounds. These studies are done in both perfused kidneys and kidney slice experiments. In addition, we are investigating the various water spaces in the kidney. The hypothermically perfused kidney, in general, responds by expanding its extracellular compartment and decreasing the intracellular compartment. Studies to further evaluate these changes as well as efforts to correct these are in progress.